Abutment swivel doorstop

ABSTRACT

A swivel bar is mounted on a door jamb to swing between a position in the path of the door to block its opening and a position retracted out of the path of door-opening movement. The stop bar can be held in door-blocking position by engagement of a rib-and-groove latch. The stop bar can be moved into latchengaged position by swinging of a keeper to move cooperating cylindrical or edgewise cams relatively which movement shifts the stop bar into latched position in opposition to the force of a latch-releasing spring.

United States Patent Lennan Jan. 21, 1975 ABUTMENT SWIVEL DOORSTOPInventor: Lyall A. McLennan, 2896 Trinity St., Vancouver 6, BC, CanadaFiled: Mar. 26, 1973 Appl. No.: 345,061

US. Cl 292/67, 292/205, 292/207, 292/290, 292/298, 292/DIG. 19

Int. Cl. E056 5/00 Field of Search 292/65, 67, 202, 205, 207, 292/208,290, 297, 298, DIG. 9, DIG. 14; 16/82, 85

References Cited UNITED STATES PATENTS 12/1897 Adams 292/205 5/1907Denny et al.. 292/67 X 11/1924 I-Ianisko 292/202 6/1950 Weissinger292/205 X FOREIGN PATENTS OR APPLICATIONS 1,210 1/1906 Great Britain292/67 368,540 3/1932 Great Britain 292/67 Primary ExaminerRobert L.Wolfe Attorney, Agent, or Firm-Robert W. Beach [57] ABSTRACT A swivelbar is mounted on a door jamb to swing between a position in the path ofthe door to block its opening and a position retracted out of the pathof door-opening movement. The stop bar can be held in door-blockingposition by engagement of a rib-andgroove latch. The stop bar can bemoved into latchengaged position by swinging of a keeper to movecooperating cylindrical or edgewise cams relatively which movementshifts the stop bar into latched position in opposition to the force ofa latch-releasing spring.

14 Claims, 19 Drawing Figures PATENTEU JANE] 9 5 86 1,726

SHEET 18F 3 PATENIED 3,861.726

sum 2 or 3 ABUTMENT SWIVEL DOORSTOP This application relates to stopsfor preventing the opening of doors and is particularly advantageous foruse with swinging doors.

A principal object of the present invention is to provide a stop whichcan be moved into door-blocking position quickly and easily.

A further object is to provide such a doorstop which is small, compactand unobtrusive yet which is strong for its size.

Another object is to provide such a doorstop which is effective andreliable to prevent the opening of a door and which can be released fromonly one side of the door. Moreover, the stop can be locked so that itcannot be opened by an unauthorized person even from the side of thedoor where the stop is accessible.

It is also an object to provide a stop construction which is simple andhas few parts, which is durable, cannot jam or otherwise readily becomeinoperative, yet which is economical to manufacture.

Still a further object is to provide such a doorstop which can beinstalled easily and quickly by an unskilled person.

FIG. 1 is a top perspective of a representative door showing a typicalinstallation of a stop of the present invention.

FIGS. 2 and 3 are side elevations of the stop mechanism viewed fromopposite sides showing the doorengageable stop member in door-clearingposition.

FIGS. 4 and 5 are plans of the stop mechanism, FIG. 4 illustrating thedoor-engageable stop member in fully retracted door-clearing positionand FIG. 5 illustrating such member in door-blocking latched position.

FIGS. 6 and 7 are bottom plans of the stop mechanism, FIG. 6 showing thestop member in fully retracted door-clearing position and FIG. 7 showingthe stop member latched in door-blocking position.

FIGS. 8 and 9 are edge elevations of the stop mechanism, FIG. 8 showingthe stop member in doorblocking unlatched position and FIG. 9 showingthe stop member in door-blocking latched position.

FIG. 10 is a fragmentary side elevation as viewed from the left of FIG.9.

FIGS. 11 and 12 are bottom and top perspectives, respectively, of oneside, and FIGS. 13 and 14 are bottom and top perspectives, respectively,of the other side of the stop mechanism, the stop member in eachinstance being in door-blocking latched position.

FIGS. 15 and 16 are exploded top and bottom perspectives, respectively,of the stop mechanism viewed from the same side.

FIG. 17 is a top perspective of a somewhat modified stop mechanism withthe stop member locked in doorlocking latched position.

FIG. 18 is a top perspective of another modified type of stop mechanismwith the door-engageable stop member in door-clearing position.

FIG. 19 is a horizontal section through such mechanism taken on linel9-l9 of FIG. 18 but with the doorengageable stop member in fullyretracted doorclearing position.

The doorstop of the present invention is most suitable for blockingopening of a closure such as a door I mounted in a frame 2 to swing intoa building or living space, but the structure could be used for blockingopening of a closure such as a sliding door or window. The importantfeature in each instance is that the stop mechanism includes aclosure-engageable stop member that can be moved between aclosure-clearing position out of the path of opening movement oftheclosure and a closure-blocking position in the path of movement of theportion of the closure engageable by the stop memher so as to preventappreciable opening movement of the closure.

The doorstop mechanism designated generally by the numeral 3 can beattached to the jamb 4 of a doorway, as shown in FIGS. 2 and 3, bysecuring the mount 5 of such mechanism to the doorjamb by screws 6. Suchscrews extend through holes 7, preferably. three or more as shown inFIG. I5, for example, in the plate portion of the stop mechanism, whichplate constitutes the mount 5. Normally such mounting plate portion willbe mortised flush into the jamb as shown in FIGS. 4 to 7 inclusive. Ifdesired the stop mechanism could be mounted on the lintel.

From the mounting plate portion 5 an upper ear 9 and a lower ear 10project in spaced, paralleL'coplanar relationship defining an opening 8therebetween. On the free ends of cars 9 and 10 are bosses II and 12,respectively, preferably of cylindrical cross-section. A bore throughthe upper boss 11 and a bore through the lower boss 12 are aligned toreceive through them a pintle 13 for mounting swingable stop and keepermembers. When stop mechanism 3 is mounted on a doorjamb, the pintle axisis parallel to the door hinge axis. The stop member 14 is a thrust orcompression member in the form of a bar having an aperture I5 extendingthrough one end portion, through which aperture the pintle passes, asshown in FIGS. 2, 3, 8, 9, l4 and 15 in particular, so that it can beswung about the pintle axis between closure-clearing and closureblockingpositions. The pintle axis is located a substantial distance from theportion of the stop member engageable by the closure, and is offsetslightly from the path of opening movement of the stop-engageableportion of the closure. A line joining the closureengageable portion ofthe stop member in closure-- blocking position and the pintle axis is ata small acute angle, such as 20 to 25, to the path of movement travelledby the stop-engageable portion of the closure toward open position,which angle is designated a in FIGS. 5 and 7. By making the angle asmall the stop mechanism can resist a greater pressure exerted on it bythe closure. Since the angle a is less than 45, the pressure of theclosure will exert on the stop member 14 a compressive force toward thepintle 13 greater than the stop member swinging force actingperpendicular to a line joining the pintle axis and the stopengageableportion of the closure. Also the mount is mounted on the closure frameso that the pintle axis is located farther from the face of the framethan it is to the closure when the closure is in its position closest tothe pintle axis.

While the stop member 14 can be swung from the closure-clearing positionof FIGS. 4 and 6 to the closure-blocking position of FIGS. 5 and 7 aboutthe axis stop member turning of pintle 13, it is desirable to hold thestop member positively in the closure blocking position. Such holdingaction can be accomplished by providing latch means for preventing thestop member from swinging relative to the mount 5 and ears 9 and 10.Such latch means includes a projection 16 in the form of a shoulderformed on the inner edge of the ear 10 in the window 8 and locatedbetween the mounting plate portion 5 and the boss on car 10. A socket inthe form of a groove 17 in the bottom of the stop member is of a size toembrace the projection 16 reasonably snugly to prevent appreciableswinging of the stop member relative to the ear when such groove isfitted over the projection.

In order to slide stop member 14 along pintle 13 to engage groove 17with projection 16, a keeper 18 is provided between the stop member 14and the ear 9. The keeper has in it a bore 19 through which the pintle13 extends so that the keeper can turn relative to the stop mechanismmount 5 and its ears 9 and 10. Cam 20 on the stop member and cam 21 onthe keeper have adjacent coacting surfaces constituting wedging edgewiseor cylinder cams so that relative rotation of the stop member 14 and thekeeper 18 between the position shown in FIG. 8 and that of FIG. 9 willspread these members apart.

To facilitate turning of the keeper 18, a handle 22 projecting radiallyfrom it is provided. Conveniently such handle includes an upwardlyprojecting fingerengageable tab. The stop member 14 is pressed towardthe keeper 18 by a helical compression spring 23 circling the pintle 13.One end of the spring is engaged with the adjacent inner side of boss 12and its other end portion is fitted in a counterbore 24 of the aperture15 though which the pintle 13 passes. When the groove 17 is engaged withthe projection 16, the end portion 25 of the keeper bar 14 will beclosest to the door 1 and, in fact, next to the closed door. Alightening cavity 26 is provided in the stop bar.

To prevent the door 1 being marred by its face striking or being pressedagainst the blocking surface 25 of the stop member 14, a faceplate 27can be mounted on the face of the door at the location engageable by thestop member surface 25. Such faceplate 27is secured to the door face byone or more screws 28, as shown in FIGS. 4 to 7 inclusive, andpreferably such faceplate is recessed by being mortised flush with theadjacent surface of the door as also shown in those figures. To preventthe opposite side of the door from being marred by the door being closedwhen the keeper member is inadvertently left or placed in door-blockingposition, a second faceplate 29 can be mounted by a screw or screws 30on the opposite face of the door. Again it is preferred that thefaceplate 29 be recessed into the door face, such as by being mortisedflush with the door face, as also shown in FIGS. 4 to 7 inclusive. Lug31 projecting below the lower edge of the side of stop member 14opposite groove 17 is engageable with projection 16 to limit the swungposition of such stop member, as shown in FIGS. 7 and 8.

In the manner described below, the stop member 14 and keeper 18 canoccupy three principal positions namely, closure-clearing position,unlatched closureblocking position and latched closure-blockingposition. The closure-clearing position is illustrated in FIGS. 4 and 6in which handle 22 of keeper l8 and stop member 14 are in registration.These members can be swung conjointly through an intermediate positionshown in FIGS. 2 and 3 into the unlatched closureblocking position shownin FIG. 8. The handle 22 can be swung relative to stop member 14 throughthe intermediate position of FIGS. 9 and 10 into the position shown inFIGS. 5, 7 and 11 through 14 to latch the stop member inclosure-blocking position.

While the stop mechanism can be mounted with either edge up depending onwhich direction the door I swings relative to the frame 2, it ispreferred that the stop mechanism be mounted so that the keeper [8 isabove the stop bar 14 as shown in FIGS. 2, 3, and 8 to 13. When thehandle 22 of keeper 18 is in registration with the stop bar 14, as shownin FIGS. 2, 3 and 8, irrespective of the swung positions of these twomembers relative to the mount 5 and ears 9 and 10, the edgewise camsurfaces 20 and 21 will be contiguous as shown in these figures and stopbar 14 will be forced as far as possible away from the ear 10 by thespring 23. Such spring presses the stop bar 14 against the keeper l8 andthereby presses the keeper against the boss II of the opposite ear 9, asalso shown in these figures.

When the stop bar 14 is held by spring 23 in such spaced relationshiprelative to the boss 12 of car 10, the grooved portion of the stop barwill clear the projection 16 so that the stop bar and keeper 18 can beconjointly swung freely about the axis of pintle 13 between theclosure-clearing limit position shown in FIGS. 4 and 6 and the unlatchedclosure-blocking limit position shown in FIG. 8. These members cannotswing conjointly farther into the opening 8 because lug 3] will engagethe side of the shoulder 16, as shown in FIGS. 7 and 8. These swingingparts are shown in an intermediate position in FIGS. 2 and 3. Thepressure of spring 23 will tend to maintain the stop bar 14 and thekeeper 18 in registration.

If the stop bar 14 and keeper 18 are swung conjointly into theclosure-blocking position shown in FIG. 8 when the door 1 is closed,force can be applied to the handle 22 of keeper 18 to swing it towardthe position shown in FIGS. 9 and 10 while the stop bar is held manuallyin the swung position shown in FIGS. 5, 7, 8, 9, 10, 11 and 12. Thewedging coaction of the edgewise cam surfaces 20 and 21 resulting fromturning of keeper 18 from the position shown in FIG. 8 to the positionshown in FIGS. 9 and 10 relative to the stop bar 14 will spread the stopbar and keeper. Since move- 7 ment of the keeper l8 axially of pintle 13is prevented by engagement of such keeper with the boss 11, thespreading of the stop bar and keeper will result in the stop bar beingmoved toward the car 10 and its boss 12, as shown in FIG. 9.

By such movement of the stop bar 14 axially of pintle 13, the groove 17of the stop bar will be pressed over the projection 16 of ear 10 to theposition shown best in FIGS. 7 and 11. As soon as the stop bar 14 isthus moved axially sufficiently so that the projection 16 enters atleast partially into the groove 17 so as to prevent the stop bar fromswinging out of closure-blocking po' sition, such stop bar need nolonger be held manually against swinging while turning of keeper 18 iscontinued by exerting force on handle 22.

Both cam surfaces 20 and 21 are semicircular inclined wedging surfaces.Cam surface 20 on stop bar 14 is upwardly inclined from the near edge asseen in FIG. 3 to the opposite edge shown in FIG. 2. A crown 32constitutes the highest portion of the cam surface which continuesbeyond such crown a short distance as a recess 32. Cam surface 21 on thekeeper 18 has an initial recess 33', followed by a downwardly projectingcrown 33, as seen in FIG. 3, followed by an upwardlyinclined surface tothe end of such cam surface seen in FIG. 2. When the keeper l8 and stopbar 14 are in the aligned oppositely-projecting relationship shown inFIGS. 9 and 10, the crowns 32 and 33 are in engagement as shown in FIG.and the stop bar and keeper have been spread apart to their maximumextent. As keeper 18 is turned farther toward the position of FIGS. 5,7, 13 and 14, the crowns 32 and 33 move relatively past the dead centerestablished by their mutual engagement, and the spring 23 moves stopmember 14 slightly toward keeper 18 and slightly away from boss 12 sothat recesses 32 and 33' are engaged. Consequently, reverse relativerotation of the cam is deterred and the keeper tends to be maintained insuch position beyond dead center to hold stop member 14 securely latchedin the closure-blocking position shown in FIGS. 5, 7 and 11 to 14 forengagement by the faceplate 27 on the door. If an attempt is made toopen the door, such engagement will prevent further opening movement ofthe door and pressure on the door will produce a compression force instop member 14.

When it is desired to shift the stop bar 14 from the closure-blockingposition of FIGS. 5, 7 and 11 to 14 to the closure-clearing positionshown in FIGS. 4 and 6, it is necessary first to swing the keeper handle22 from the position of FIGS. 5, 7 and 11 to 14, fully toward the doorthrough the position of FIGS. 9 and 10 into the position of FIG. 8.While the keeper handle 22 is being swung from the position of FIG. 9 tothe position of FIG. 8, the spring 23 will shift the stop bar 14 progressively axially along pintle 13 from the position of FIG. 9 toward theposition of FIG. 8.

When the keeper handle 22 has been brought into registration with thestop bar 14 as shown in FIG. 8, such stop bar will have been shiftedaxially of pintle l3 sufficiently so that groove 17 will clear theprojection 16. Next the keeper and stop bar can be swung conjointly inthe opposite direction away from the door from the position of FIG. 8 tothe closure-clearing position of FIGS. 2 and 3 or even farther to theclosureclearing position of FIGS. 4 and 6. The door 1 can then be openedfreely without interference by the stop bar. If the stop bar should beswung into closure-blocking position when the door 1 is opened and thedoor is swung toward closed position without the stop bar being swunginto closure-clearing position the faceplate 29 will strike the side ofstop bar 14 opposite its groove 17. While the door cannot be closed aslong as the stop bar is in such closure-blocking position, engagement ofthe face plate 29 with the stop bar will prevent the margin of the outerdoor face from becoming marred.

A double swinging action is also required to shift the stop bar from theclosure-clearing position to the closure-blocking position. The keeperand stop bar are swung conjointly toward the door to the position ofFIG. 8 and then the keeper alone is swung away from the door into theposition of FIGS. 5, 7 and 11 to 14.

Instead of relying on the swiveled keeper alone to maintain the stop barin closure-blocking position relative to the stop mechanism mount suchstop bar can be locked positively in its closure-blocking position ifdesired. In FIG. 17 a heavy-duty swivel doorstop mechanism isillustrated which has parts corresponding to the parts of the doorstopmechanism described above but which parts are larger and stronger. Inthis structure the base 34 can be secured to a doorjamb by screws orbolts passing through holes 35. Ears 9' and 10 project in spacedrelationship from the base 34 and have bosses which are bored to receivethe pintle 13. Such pintle extends through a bore in the stop bar 14.

The adjacent portions of the stop bar 14 and a keeper 18' havecooperating edgewise or cylinder cams 20' and 21 which coact duringrelative turning of the stop bar and keeper to spread these parts.Turning of the keeper 18' relative to the stop bar 14' is effected byswinging handle 22 integral with the keeper. It is not necessary, eitherin the structure of this stop mechanism or in that described inconnection with FIGS. 2 through 16, to provide a spring for urging thestop bar away from the ear 10 or 10' to disengage the latch groove froma latch edge. Instead the stop bar can be shifted manually, axially ofthe pintle into unlatched position. The spring, however, provides a moreconvenient operation for shifting the stop bar from closureblocking toclosure-clearing position.

Instead of or in addition to relying on the keeper 18' to hold the stopbar 14' in a position such that its latch groove is in latchingengagement with the latch edge, an eye can be provided between the stopbar and the ear 9' into which a spacer member can be inserted to limitmovement of the stop bar 14 axially of the pintle 13. In FIG. 16 the eyeis shown as being formed by an arcuate notch 36 in the edge of ear 9adjacent to the stop bar 14'. The shackle 37 of a padlock 38 is shown ashaving been inserted through such eye to serve as the spacer member forlimiting axial movement of the stop. bar 14'. By application of apadlock in this manner, the stop mechanism is held positively inclosure-blocking position until the padlock is removed.

In the alternative construction shown in FIGS. 18 and 19 most of thecomponents can be identical with those described in connection withFIGS. 2 to 16 inclusive. In this instance, however, the mount 5' differsfrom the mount of the stop mechanisms described above in that such mountincludes features of a conventional strike for a door lock. Instead ofthe doorstop mechanism being entirely separate from the door lock, themount of the stop mechanism is integrated with the strike of the doorlock to reduce the amount of hardware and thus installation labor in newconstruction.

In order to provide a stop bar and keeper of adequate strength, thewidth of the opening 8 between the ear 9 and the projection 16 is likelyto be greater than the width of the bolt 39 of lock 40. Consequently,the edge of the opening 8 parallel to and remote from pintle I3 isinclined to form a ramp 41 along which the end of bolt 39 can slide towedge the bolt out of the opening 8. At the side of the ramp 41 remotefrom pintle I3 is another opening 42 into which the end of the bolt 39can snap as the door is closed to hold the door in the position shown inFIG. 19. The mount 5' is held in proper position on the doorjamb byscrews or bolts extending through apertures 7' in the mount. When thestop bar is in a closure-clearing position such as shown in FIG. 18 orFIG. [9, bolt can pass stop mechanism 3. When the door is closed, thestop bar can be swung between closure-blocking and closure-clearingpositions in the manner described above in connection with FIGS. 2 to 16and will block opening of the door by engagement of faceplate 27 withthe stop bar 14 in the same manner as described above.

If reliance were placed on the lock alone. to secure a door a thin,stiff sheet could be inserted between the edge of the door 1 and thedoorjamb 4 from the right side as seen in FIG. 19 and wedge the inclinedend of bolt 39 out of the window 42 of the mount However, with the stopmechanism of the present invention, even if such a sheet were forced onthrough the space between the door edge and the jamb into engagementwith the stop bar 14, such stop bar could not be dislodged because ofthe latching engagement between its groove 17 and the projection 16.Such engagement is maintained by the keeper 18 being in its positionpast dead center, as shown in FIGS. 11 to 14, inclusive, or by theinterposition of some other type of spacer between the stop bar 14 andthe ear 9, such as the shackle of a padlock, as discussed in connectionwith FIG. 17.

I claim:

1. In abutment stop mechanism for blocking opening movement of a closureincluding a stop member and a mount separate from the closure, mountedadjacent to but independently of the closure in closed position andsupporting the stop member for turning about a stop member turning axisbetween a closure-blocking position and a closure-clearing position, inwhich closureblocking position the stop member obstructs a predeterminedopening-movement path of a stop-engageable portion of the closure and aclosure-engageable portion of the stop member is engageable by suchstopengageable portion of the closure to limit movement of suchstop-engageable portion along such predetermined opening-movement path,and in which closureclearing position the stop member is out of theopening-movement path of the stop-engageable portion of the closure, theclosure-engageable portion of the stop member being located asubstantial distance from the stop member turning axis, the improvementcomprising the mount being mounted with the stop member turning axissubstantially perpendicular to and offset slightly from suchpredetermined opening-movement path of the stop-engageable portion ofthe closure and located so that a line joining such stop member turningaxis and the closure-engageable portion of the stop member inclosure-blocking position is at an angle to such predeterminedopening-movement path of the stop-engageable portion of the closure ofless than 45 so that pressure of the stop-engageable portion of theclosure on the stop member will exert on the stop memher a compressiveforce toward the stop member turning axis greater than the stop memberswinging force acting perpendicular to a line joining the stop memberturning axis and the stop-engageable portion of the closure when theclosure is in its position closest to the stop member turning axis.

2. The stop mechanism defined in claim 1, and latch means for securingthe stop member in its closureblocking position incluidng a latch groovein the stop member and a latch projection carried by the mount andlocated for engagement in said groove when the stop member is inclosure-blocking position.

3. In abutment stop mechanism for blocking opening movement of a closureincluding a stop member and a mount separate from the closure, mountedadjacent to such stop-engageable portion along such predeterminedopening-movement path, and in which closureclearing position the stopmember is out of the opening-movement path of the stop-engageableportion of the closure, the improvement comprising latch meansinterengageable between the stop member and the mount for securing thestop member in its closureblocking position and including a latch grooveand a latch projection located for locking interengagement when the stopmember is in closure-blocking position, and cam means turnable relativeto the mount and the stop member for effecting movement of the stopmember axially relative to the mount to engage said latch projection insaid latch groove.

4. In abutment stop mechanism for blocking opening movement of a closureincluding a stop member and a mount separate from the closure, mountedadjacent to but independently of the closure in closed position andsupporting the stop member for turning about a stop member turning axisbetween a closure-blocking position and a closure-clearing position, inwhich closureblocking position the stop member obstructs a predeterminedopening-movement path of a stop-engageable portion of the closure and aclosure-engageable portion of the stop member is engageable by suchstopengageable portion of the closure to limit movement of suchstop-engageable portion along such predetermined opening-movement path,and in which closureclearing position the stop member is out of theopening-movement path of the stop-engageable portion of the closure, theimprovement comprising latch means interengageable between the stopmember and the mount for securing the stop member in its closureblockingpostion and including a latch groove and a latch projection located forlocking interengagcment when the stop member is in closure-blockingposition, and spring means urging the stop member to move relative tothe mount in the direction to disengage said latch groove and said latchprojection.

5. The stop mechanism defined in claim 4, in which the spring meansincludes a helical compression spring engaged between the mount and thestop member and arranged concentrically with the stop member turningaxis.

6. The stop mechanism defined in claim 4, and cam means turnablerelative to the mount and the stop member for effecting movement of thestop member axially relative to the mount in opposition to the force ofthe spring means to engage the latch projection in the latch groove.

7. The stop mechanism defined in claim 1, in which the closure ismounted in a frame, and the mount is mounted on the closure frame sothat the stop member turning axis is located farther from the face ofthe frame than it is to the closure when the closure is in its positionclosest to the stop member turning axis.

8. The stop mechanism defined in claim 2, and cam means turnablerelative to the mount and the stop member for effecting movement of thestop member axially relative to the mount to engage the latch projectionin the latch groove.

9. The stop mechanism defined in claim 8, in which the cam means includecoacting edgewise cams relatively rotatable about the stop memberturning axis.

10. The stop mechanism defined in claim 9, in which at least one of theedgewise cams is crowned and the cams are relatively turnable in onedirection to move her and arranged concentrically with the stop memberturning axis.

13. The stop mechanism defined in claim 2, and

shackle means for holding the stop member in position with the latchgroove and latch projection engaged.

14. The stop mechanism defined in claim 1, in which the mount includes alock strike.

1. In abutment stop mechanism for blocking opening movement of a closureincluding a stop member and a mount separate from the closure, mountedadjacent to but independently of the closure in closed position andsupporting the stop member for turning about a stop member turning axisbetween a closure-blocking position and a closure-clearing position, inwhich closure-blocking position the stop member obstructs apredetermined openingmovement path of a stop-engageable portion of theclosure and a closure-engageable portion of the stop member isengageable by such stop-engageable portion of the closure to limitmovement of such stop-engageable portion along such predeterminedopeningmovement path, and in which closure-clearing position the stopmember is out of the opening-movement path of the stop-engageableportion of the closure, the closure-engageable portion of the stopmember being located a substantial distance from the stop member turningaxis, the improvement comprising the mount being mounted with the stopmember turning axis substantially perpendicular to and offset slightlyfrom such predetermined opening-movement path of the stop-engageableportion of the closure and located so that a line joining such stopmember turning axis and the closure-engageable portion of the stopmember in closure-blocking position is at an aNgle to such predeterminedopening-movement path of the stop-engageable portion of the closure ofless than 45* so that pressure of the stop-engageable portion of theclosure on the stop member will exert on the stop member a compressiveforce toward the stop member turning axis greater than the stop memberswinging force acting perpendicular to a line joining the stop memberturning axis and the stop-engageable portion of the closure when theclosure is in its position closest to the stop member turning axis. 2.The stop mechanism defined in claim 1, and latch means for securing thestop member in its closure-blocking position incluidng a latch groove inthe stop member and a latch projection carried by the mount and locatedfor engagement in said groove when the stop member is inclosure-blocking position.
 3. In abutment stop mechanism for blockingopening movement of a closure including a stop member and a mountseparate from the closure, mounted adjacent to but independently of theclosure in closed position and supporting the stop member for turningabout a stop member turning axis between a closure-blocking position anda closure-clearing position, in which closure-blocking position the stopmember obstructs a predetermined opening-movement path of astop-engageable portion of the closure and a closure-engageable portionof the stop member is engageable by such stop-engageable portion of theclosure to limit movement of such stop-engageable portion along suchpredetermined opening-movement path, and in which closure-clearingposition the stop member is out of the opening-movement path of thestop-engageable portion of the closure, the improvement comprising latchmeans interengageable between the stop member and the mount for securingthe stop member in its closure-blocking position and including a latchgroove and a latch projection located for locking interengagement whenthe stop member is in closure-blocking position, and cam means turnablerelative to the mount and the stop member for effecting movement of thestop member axially relative to the mount to engage said latchprojection in said latch groove.
 4. In abutment stop mechanism forblocking opening movement of a closure including a stop member and amount separate from the closure, mounted adjacent to but independentlyof the closure in closed position and supporting the stop member forturning about a stop member turning axis between a closure-blockingposition and a closure-clearing position, in which closure-blockingposition the stop member obstructs a predetermined opening-movement pathof a stop-engageable portion of the closure and a closure-engageableportion of the stop member is engageable by such stop-engageable portionof the closure to limit movement of such stop-engageable portion alongsuch predetermined opening-movement path, and in which closure-clearingposition the stop member is out of the opening-movement path of thestop-engageable portion of the closure, the improvement comprising latchmeans interengageable between the stop member and the mount for securingthe stop member in its closure-blocking postion and including a latchgroove and a latch projection located for locking interengagement whenthe stop member is in closure-blocking position, and spring means urgingthe stop member to move relative to the mount in the direction todisengage said latch groove and said latch projection.
 5. The stopmechanism defined in claim 4, in which the spring means includes ahelical compression spring engaged between the mount and the stop memberand arranged concentrically with the stop member turning axis.
 6. Thestop mechanism defined in claim 4, and cam means turnable relative tothe mount and the stop member for effecting movement of the stop memberaxially relative to the mount in opposition to the force of the springmeans to engage the latch projection in the latch groove.
 7. The stopmechanism defined in claim 1, in which the closure is mounted in afRame, and the mount is mounted on the closure frame so that the stopmember turning axis is located farther from the face of the frame thanit is to the closure when the closure is in its position closest to thestop member turning axis.
 8. The stop mechanism defined in claim 2, andcam means turnable relative to the mount and the stop member foreffecting movement of the stop member axially relative to the mount toengage the latch projection in the latch groove.
 9. The stop mechanismdefined in claim 8, in which the cam means include coacting edgewisecams relatively rotatable about the stop member turning axis.
 10. Thestop mechanism defined in claim 9, in which at least one of the edgewisecams is crowned and the cams are relatively turnable in one direction tomove the crown beyond a predetermined position to deter relative turningof the cams in the opposite direction.
 11. The stop mechanism defined inclaim 2, and spring means urging the stop member to move relative to themount in the direction to disengage the latch groove and the latchprojection.
 12. The stop mechanism defined in claim 11, in which thespring means includes a helical compression spring engaged between themount and the stop member and arranged concentrically with the stopmember turning axis.
 13. The stop mechanism defined in claim 2, andshackle means for holding the stop member in position with the latchgroove and latch projection engaged.
 14. The stop mechanism defined inclaim 1, in which the mount includes a lock strike.